I think for me, I'd be Ok, but I'd want to have some sort of agreement (in writing) that the original digital file was going to be destroyed after the commission was completed.
All 1 artist, I really am not concerned about the process, how many people ask artists if they use strait edges, circle patterns, photo-reference... so many other tools in their arsenal, why take away 1? The only reason I can think of, is the one above.
I just want to know that mine is really one of a kind, vs "template x73-batman_on_a_garyole_while_its_raining"